MRP Processing of Plan Materials at Operation Start

When MRP generates a PLN to satisfy a demand, it always plans the materials to be due at the start of the job. For jobs and production schedule releases, MRP considers the Plan Materials at Operation Start field when the following conditions are true:

• The job or production schedule release has been scheduled (that is, the Scheduled field is selected on the Job Orders or Production Schedule Items form)
• The Use Scheduled Times in Planning parameter is selected

This table describes scenarios where the Plan Materials at Operation Start field is not selected:

Job Scheduled AND Use Scheduled Times in Planning selected?	Job Start Date	Materials are due at
No	Not blank	Job's start date
No	Blank	Job's End Date - Fixed Lead Time + (Variable Lead Time * Qty)
Yes	n/a	Job's internal projected start date (calculated by the Scheduler--not displayed elsewhere)

This table describes scenarios where the Plan Materials at Operation Start field is selected:

Job Scheduled AND Use Scheduled Times in Planning selected?	Operation Start Date	Job Start Date	Materials are due at
Yes	Not blank	n/a	Operation Start Date
Yes	Blank	n/a	Job's internal projected start date (calculated by the Scheduler--not displayed elsewhere)
No	n/a	Not blank	Job Start Date
No	n/a	Blank	Job's End date - Fixed Lead Time + (Variable Lead Time * Qty)